The significant rise in commercial fertilizer prices over the past few years has livestock producers looking at manure differently. While it is generally acknowledged that manure yields some nutrients for crop growth and organic matter for soil conditioning, farmers are starting to ask "what is my manure really worth"?
Are there really enough nutrients in the manure to replace fertilizer? The nutrient and dry matter content of manure will depend on a number of variables, including: livestock type; livestock genetics; feed ingredients; type of bedding; amount of washwater added; where in the storage the manure is stored (top, bottom, middle).
By knowing exactly how much nutrients are supplied by the manure, you can accurately reduce the amount of fertilizer needed to meet crop requirements. A manure sample showing the total nitrogen, ammonium-nitrogen, phosphorus, potassium and dry matter content will give you the values you need to reduce your fertilizer amount and save you money. Manure sampling over several years is recommended in order to help create a database of the nutrients generated on your farm.
What is the cost for a manure sample? A basic manure sample will cost around $35.00. The sample will give the nutrient values for : total nitrogen; ammonium-nitrogen; phosphorus; potassium; and, dry matter content.
What is the value of the nutrients in the manure? While the nutrient content of manure does depend on a number of variables and the annual price of fertilizer does fluctuate, the table below shows the potential for savings. The table uses average nutrient contents for livestock manure and 2009 projected fertilizer prices.
Manure Type Available N Available P Potassium Total Nutrient Value*
*Based on : Urea @ $850/mt = $0.84/lb, 11-52-0 MAP @ 1200/mt = $1.05/lb, Potash @ $1000/mt = $0.73/lb
The table clearly shows the significant value of the nutrients found in manure. When you compare the nutrient values in the manure with the $35 cost to do the sampling, it is clear that sampling is a good investment of time and money. By investing $35 in a manure sample, you are gaining the knowledge and confidence to reduce or eliminate the supplemental fertilizer you would need to spread on your land.
Are there more opportunities to save money? Combining manure tests with regular soil sampling is an even better investment as fields with low nutrient levels can be targeted to receive more manure and fields with high nutrient levels can receive reduced amount of manure. The more information you use to make application decisions, the greater confidence you will have that your crops are receiving the right amount of nutrients and that you are saving money by not applying excess nutrients.